Distance measuring device and light-emitting module thereof

ABSTRACT

A distance measuring device for measuring the distance to an object is provided, including a light-emitting module, a driving assembly disposed in the light-emitting module, and a light-receiving module. The light-emitting module has a housing, a light source disposed in the housing, a light grating element, and an optical path adjuster. The light source emits a measuring light through the optical path adjuster and the light grating element. The driving assembly can drive the optical path adjuster or the light grating element to move relative to the housing. The light-receiving module receives the measuring light which is reflected by the object to obtain distance information of the object.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation application of U.S. patentapplication Ser. No. 16/164,193, filed Oct. 18, 2018, which claimspriority of provisional U.S. Patent Application Ser. No. 62/573,918,filed on Oct. 18, 2017, provisional U.S. Patent Application Ser. No.62/621,967, filed on Jan. 25, 2018, and China Patent Application No.201811191146.3 filed on Oct. 12, 2018, the entirety of which areincorporated by reference herein.

BACKGROUND OF THE INVENTION Field of the Invention

The application relates in general to a distance measuring device, andin particular, to a distance measuring device having a light gratingelement.

Description of the Related Art

Conventional camera devices provided in cell phones or tablet computerscan capture 2D images, but they usually cannot capture 3D images orestablish a 3D model of an object. Recently, with the progress beingmade in Virtual Reality (VR) and Augmented Reality (AR) technologies, todesign a distance measuring device that can obtain color and distanceinformation of an object in 3D space has become a popular issue.

BRIEF SUMMARY OF INVENTION

In view of the aforementioned problems, the object of the invention isto provide a distance measuring device for measuring the distance to anobject, including a light-emitting module, a driving assembly disposedin the light-emitting module, and a light-receiving module. Thelight-emitting module has a housing, a light source disposed in thehousing, a light grating element, and an optical path adjuster. Thelight source emits a measuring light through the optical path adjusterand the light grating element. The driving assembly can drive theoptical path adjuster or the light grating element to move relative tothe housing. The light-receiving module receives the measuring lightwhich is reflected by the object to obtain distance information of theobject.

BRIEF DESCRIPTION OF DRAWINGS

The invention can be more fully understood by reading the subsequentdetailed description and examples with references made to theaccompanying drawings, wherein:

FIG. 1 shows a perspective diagram of a distance measuring device inaccordance with an embodiment of the invention.

FIG. 2 shows a side view of the distance measuring device in FIG. 1.

FIG. 3 shows an exploded diagram of the light-emitting module 1 in FIGS.1 and 2.

FIGS. 4 and 5 are two perspective diagrams of the movable mechanism 13in FIG. 3 from different viewing angles.

FIGS. 6 and 7 are cross-sectional views showing the light-emittingmodule 1 and a part of the circuit board 4 after assembly.

FIG. 8 is a perspective diagram showing a holder H, a collimating lens Ldisposed in the holder H, and several coils C1 and C2 disposed on thelateral sides of the holder H in accordance with another embodiment ofthe invention.

FIG. 9 is a perspective diagram showing relative position of the holderH, the collimating lens L, and the coils C1 and C2 in FIG. 8, andseveral magnetic elements M1 and M2 after assembly.

FIG. 10 is cross-sectional view of a light-emitting module 1 comprisingthe holder H, the collimating lens L, the coils C1 and C2, and themagnetic elements M1 and M2 in FIG. 9 which are assembled with othercomponents.

FIG. 11 is a perspective diagram showing a holder H, a light gratingelement 11 disposed in the holder H, and several coils C1 and C2disposed on the lateral sides of the holder H in accordance with anotherembodiment of the invention.

FIG. 12 is a perspective diagram showing relative position of the holderH, the light grating element 11, the coils C1 and C2, and severalmagnetic elements M1 and M2 after assembly.

FIG. 13 is cross-sectional view of the holder H, the light gratingelement 11, the coils C1 and C2, and the magnetic elements M1 and M2 inFIG. 12 which are assembled with other components to form of thelight-emitting module 1.

FIG. 14 is a cross-sectional view of the distance measuring device inFIG. 1, wherein some parts in the light-emitting module 1.

FIG. 15 is a cross-sectional view of the distance measuring device 1 inaccordance with another embodiment of the invention.

FIG. 16 is a top view of the light source 19 which comprises a pluralityof light-emitting units 19U arranged in a matrix.

FIG. 17 is a top view of the light filter 23 which comprises a pluralityof light filtering units 23U arranged in a matrix.

FIG. 18 is a top view of the image sensor 24 which comprises a pluralityof photosensitive units 24U arranged in a matrix.

FIG. 19 is a perspective diagram showing a light-emitting module 1 inaccordance with another embodiment of the invention.

FIG. 20 is a perspective diagram showing a light-emitting module 1 inaccordance with another embodiment of the invention.

FIG. 21 is a perspective diagram showing a light-emitting module 1 inaccordance with another embodiment of the invention.

FIG. 22 is a perspective diagram showing the light grating element 11 ofthe light-emitting module 1 attached to a surface of the reflectingelement R2.

FIG. 23 is a perspective diagram showing the optical lens 21 of thelight-receiving module 2 attached to a surface of the reflecting elementR2.

FIG. 24 is a perspective diagram showing the optical lens 31 of theimage capturing module 3 attached to a surface of the reflecting elementR2.

DETAILED DESCRIPTION OF INVENTION

The making and using of the embodiments of the distance measuring deviceare discussed in detail below. It should be appreciated, however, thatthe embodiments provide many applicable inventive concepts that can beembodied in a wide variety of specific contexts. The specificembodiments discussed are merely illustrative of specific ways to makeand use the embodiments, and do not limit the scope of the disclosure.

Unless defined otherwise, all technical and scientific terms used hereinhave the same meaning as commonly understood by one of ordinary skill inthe art to which this invention belongs. It should be appreciated thateach term, which is defined in a commonly used dictionary, should beinterpreted as having a meaning conforming to the relative skills andthe background or the context of the present disclosure, and should notbe interpreted in an idealized or overly formal manner unless definedotherwise.

In the following detailed description of the preferred embodiments,reference is made to the accompanying drawings, and in which specificembodiments of which the invention may be practiced are shown by way ofillustration. In this regard, directional terminology, such as “top,”“bottom,” “left,” “right,” “front,” “back,” etc., is used with referenceto the orientation of the figures being described. The components of thepresent invention can be positioned in a number of differentorientations. As such, the directional terminology is used for thepurposes of illustration and is in no way limiting.

Referring to FIGS. 1 and 2, FIG. 1 shows a perspective diagram of adistance measuring device in accordance with an embodiment of theinvention, and FIG. 2 shows a side view of the distance measuring devicein FIG. 1 when detecting an object 5. As shown in FIGS. 1 and 2, thedistance measuring device may be disposed on a cell phone, tabletcomputer, or other portable electronic equipment, and it primarilycomprises a light-emitting module 1, a light-receiving module 2, animage capturing module 3, and a circuit board 4. Here, thelight-emitting module 1, the light-receiving module 2, and the imagecapturing module 3 are disposed on the circuit board 4.

Still referring to FIGS. 1 and 2, during operation of the distancemeasuring device, a light source inside the light-emitting module 1 canemit a measuring light L1 through a light grating element 11 on the topof the light-emitting module 1 to an object 5, and the measuring lightL1 is then reflected by the object 5 and generate two reflected lightsL2 and L3 at different angles. The reflected light L2 propagates throughan optical lens 21 and an IR pass filter to an image sensor inside thelight-receiving module 2, and the reflected light L3 propagates throughan optical lens 31 and an IR cut filter to another image sensor insidethe image capturing module 3.

It should be noted the light-receiving module 2 is used for receivinginfrared light reflected by the object 5, so as to obtain distance ordepth information of the object 5. The image capturing module 3 is usedfor receiving visible light reflected by the object 5, so as to obtain acolor image and related color information of the object 5.

In some embodiments, the measuring light L1 may be projected on theobject 5 to form a plurality of light spots in a matrix. As mentionedabove, the receiving module 2 and the image capturing module 3 canrespectively receive infrared light and visible light which arereflected by the object 5, whereby a 3D model with color information ofthe object 5 can be established.

FIG. 3 shows an exploded diagram of the light-emitting module 1 in FIGS.1 and 2. As shown in FIG. 3, the light-emitting module 1 primarilycomprises a light grating element 11, a hollow housing 12, a movablemechanism 13, a circuit unit 14, a base 15, a support 16, a beamexpander 17, a substrate 18, and a light source 19. The light gratingelement 11 may comprise a Fresnel lens or Diffraction Optical Element(DOE) disposed above the housing 12. The movable mechanism 13, thecircuit unit 14, the base 15 are received in an interior space of thehousing 12.

In this embodiment, the beam expander 17 is disposed on the support 16,the light source 19 is disposed on the substrate 18, and the base 15 andthe support 16 are stacked on the substrate 18. The housing 12 and thecircuit unit 14 are affixed to the base 15, wherein the circuit unit 14comprises a fine pattern coil 141 (FP-Coil) and a flexible printedcircuit board 142. The fine pattern coil 141 can be electricallyconnected to an external circuit via the flexible printed circuit board142. Additionally, the movable mechanism 13 is movably disposed in thehousing 12, wherein a collimating lens L is disposed at the center ofthe movable mechanism 13.

Each of the collimating lens L and the beam expander 17 can be used asan optical path adjuster for guiding light and adjusting the opticalpath of the measuring light L1 from the light source 19 to the lightgrating element 11. Therefore, the measuring light L1 can be guided tosequentially propagate through the beam expander 17, the collimatinglens L, and the light grating element 11 to the object 5. Subsequently,the measuring light L1 can be reflected by the object 5 to the receivingmodule 2 and the image capturing module 3, thereby obtaining distanceand color information of the object 5 in 3D space.

FIGS. 4 and 5 are two perspective diagrams of the movable mechanism 13in FIG. 3 from different viewing angles. As shown in FIGS. 4 and 5, themovable mechanism 13 primarily comprises a frame F, a holder H, aplurality of magnetic elements M (e.g. magnets) affixed to the frame F,at least a coil C surrounding the holder H, and a collimating lens Ldisposed at the center of the holder H.

In this embodiment, the holder H is connected to the frame F via aplurality of upper spring sheets S1 and a lower spring sheet S2, so thatthe holder H and the collimating lens L are movable relative to thehousing 12 along the Z axis (first axis). Moreover, the frame F isconnected to the circuit unit 14 via several thin and flexible metalmembers W, so that the holder H and the frame F can move relative to thecircuit unit 14 and the base 15 along a horizontal directionperpendicular to the Z axis.

It should be noted that at least one of the magnetic elements M and thecoil C on the holder H can constitute a driving assembly for driving theholder H and the collimating lens L to move. In some embodiments, thereceiving module 2 or the image capturing module 3 can receive andtransfer the light reflected by the object 5 into an electrical signal,and the electrical signal can be transferred to a control unit (notshown) via the circuit board 4. If the intensity of the light receivedby the receiving module 2 or the image capturing module 3 is less than apredetermined value, the control unit can generate a driving signal tothe driving assembly (e.g. applying a current signal to the coil C).Thus, an electromagnetic force between the magnetic element M the coil Ccan be produced, and the holder H and the collimating lens L can bedriven to move relative to the frame F and the housing 12 along the Zaxis (first axis), whereby the quality and intensity of the measuringlight L1 can be efficiently improved.

Similarly, at least one of the magnetic elements M and the fine patterncoil 141 below the magnetic element M may also constitute a drivingassembly for driving the holder H, the collimating lens L, and the frameF to move. For example, when the object 5 is located outside of themeasuring range of the measuring light L1, the receiving module 2 or theimage capturing module 3 may not able to receive light to establish theprofile of the object 5. In this case, the control unit can generate adriving signal to the driving assembly (e.g. applying a current signalto the fine pattern coil 141) so that an electromagnetic force betweenthe magnetic element M the fine pattern coil 141 can be generated.Therefore, the holder H, the collimating lens L, and the frame F can bedriven to move relative to the housing 12 along the X or Y axis (secondaxis), whereby the quality and emitting angle of the measuring light L1can be improved and adjusted.

FIGS. 6 and 7 are cross-sectional views showing the light-emittingmodule 1 and a part of the circuit board 4 after assembly. As shown inFIGS. 6 and 7, the light source 19, the beam expander 17, thecollimating lens L, and the light grating element 11 are sequentiallyarranged along the Z axis. An electromagnetic force can be generatedbetween the magnetic elements M and the coil C to drive the holder H andthe collimating lens L to move relative to the frame F and the housing12 along the Z axis (first axis). Moreover, the magnetic elements M andthe fine pattern coil 141 can also produce an electromagnetic force todrive the holder H, the collimating lens L, and the frame F to moverelative to the housing 12 along the X or Y axis (second axis), thusappropriately adjusting the emitting angle and improving the quality andof the measuring light L1.

FIG. 8 is a perspective diagram showing a holder H, a collimating lens Ldisposed in the holder H, and several coils C1 and C2 disposed on thelateral sides of the holder H in accordance with another embodiment ofthe invention. FIG. 9 is a perspective diagram showing relative positionof the holder H, the collimating lens L, and the coils C1 and C2 in FIG.8, and several magnetic elements M1 and M2 after assembly. FIG. 10 iscross-sectional view of a light-emitting module 1 comprising the holderH, the collimating lens L, the coils C1 and C2, and the magneticelements M1 and M2 in FIG. 9 which are assembled with other components.

As shown in FIGS. 8-10, the coils C1 and C2 have an oval structure andare disposed on different sides of the holder H. The two coils C1 aredisposed on opposite sides of the quadrilateral holder H, correspondingto the magnetic elements M1 (e.g. magnets) affixed to the frame F or thehousing 12. The other four coils C2 are respectively disposed at thefour corners of the holder H, corresponding to the four magneticelements M2 (e.g. magnets) affixed to the frame F or the housing 12.

As the holder H is suspended within the frame F via the upper and lowerspring sheets S1 and S2, an electromagnetic force can be generatedbetween the magnetic elements M and the coils C1 when an electricalcurrent is applied to the coils C1. Hence, the holder H and thecollimating lens L can be driven to move relative to the frame F and thehousing 12 along the Z axis (first axis). When the object 5 is outsideof the measuring range of the measuring light L1, different magnitudesof electrical currents may be individually applied to the coils C2 atthe corners of the holder H, so that a torque is exerted on the holder Hand the collimating lens L. As a result, the holder H and thecollimating lens L can rotate relative to the frame F and the housing 12around the rotary axis Rx or Ry (as the arrows indicate in FIG. 8),thereby adjusting the emitting angle and improving the quality of themeasuring light L1. In this embodiment, the rotary axes Rx and Ry aresubstantially perpendicular to the optical axis O1 of the collimatinglens L and the Z axis (first axis).

FIG. 11 is a perspective diagram showing a holder H, a light gratingelement 11 disposed in the holder H, and several coils C1 and C2disposed on the lateral sides of the holder H in accordance with anotherembodiment of the invention. FIG. 12 is a perspective diagram showingrelative position of the holder H, the light grating element 11, thecoils C1 and C2, and several magnetic elements M1 and M2 after assembly.FIG. 13 is cross-sectional view of the holder H, the light gratingelement 11, the coils C1 and C2, and the magnetic elements M1 and M2 inFIG. 12 which are assembled with other components to form of thelight-emitting module 1.

The light-emitting module 1 in FIG. 13 is different from FIG. 10 in thatthe collimating lens L is disposed on the base 15, and the light gratingelement 11 is disposed in the holder H. The frame F in FIG. 13 affixedto the inner surface of the housing 12, and the holder H is connected tothe frame F via the upper and lower springs S1 and S2, so that theholder H is suspended within the frame F.

As shown in FIGS. 11 and 12, the coils C1 and C2 in this embodiment havean oval structure and are disposed on different sides of the holder H.The two coils C1 are disposed on opposite sides of the quadrilateralholder H, corresponding to the magnetic elements M1 (e.g. magnets)affixed to the frame F or the housing 12. The other four coils C2 arerespectively disposed at the four corners of the holder H, correspondingto the four magnetic elements M2 (e.g. magnets) affixed to the frame For the housing 12.

When an electrical current is applied to the coils C1, anelectromagnetic force can be generated between the magnetic elements Mand the coils C1 to move the holder H and the light grating element 11relative to the frame F and the housing 12 along the Z axis (firstaxis). When the object 5 is outside of the measuring range of themeasuring light L1, different magnitudes of electrical currents may beapplied to the coils C2 at the corners of the holder H, so that a torqueis exerted on the holder H and the light grating element 11. As aresult, the holder H and the light grating element 11 can rotaterelative to the frame F and the housing 12 around the rotary axis Rx orRy (as the arrows indicate in FIG. 11), thereby adjusting the emittingangle and improving the quality of the measuring light L1. In thisembodiment, the rotary axes Rx and Ry are substantially perpendicular tothe optical axis O2 of the light grating element 11 and the Z axis(first axis).

In some embodiments, the beam expander 17 or other optical path adjustercan also be disposed on the holder H which is suspended within the frameF. Hence, the beam expander 17 or other optical path adjuster can bedriven to move along X, Y or Z axis, or rotate around the rotary axis Rxor Ry, whereby the quality, intensity, and emitting angle of themeasuring light L1 can be efficiently improved.

FIG. 14 is a cross-sectional view of the distance measuring device inFIG. 1, wherein some parts in the light-emitting module 1, thelight-receiving module 2, and the image capturing module 3 are omittedfrom FIG. 14 for clarity. As shown in FIG. 14, the light source 19inside the light-emitting module 1 can emit the measuring light L1substantially along the Z axis (first axis) through beam expander 17,the collimating lens L, and the light grating element 11, so as to formlight spots on the object 5 (FIG. 2) in a matrix. The measuring light L1is then reflected by the object 5, wherein the reflected light L2propagates through the optical lens 21 and a light filter 23 (e.g.infrared-pass filter) to an image sensor 24 inside the light-receivingmodule 2, and the reflected light L3 propagates through the optical lens31 and a light filter 33 (e.g. infrared-cut filter) to an image sensor34 inside the image capturing module 3.

It should be noted that the light-receiving module 2 can receiveinfrared light which is reflected by the object 5, so as to obtain anon-color image with distance/depth information of the object 5.Additionally, the image capturing module 3 can receive visible lightwhich is reflected by the object 5, so as to obtain a color image andrelated color information of the object 5. Specially, thelight-receiving module 2 and the image capturing module 3 can transferthe non-color image and the color image to an image processing module(not shown) via the circuit board 4, and the image processing module cancombine the color image with the non-color image to generate a 3Dcomposite image, whereby a 3D model with color information of the object5 can be established.

FIG. 15 is a cross-sectional view of the distance measuring device 1 inaccordance with another embodiment of the invention, wherein the imagecapturing module 3 in FIG. 14 is omitted from FIG. 15, and the lightsource 19 inside the light-emitting module 1 can emit both infraredlight and visible light. Moreover, the image sensor 24 inside thereceiving module 2 can receive both infrared light and visible lightwhich are reflected by the object 5.

In this embodiment, as shown in FIG. 16, the light source 19 in thelight-emitting module 1 comprises a plurality of light-emitting units19U arranged in a matrix. Each of the light-emitting units 19U has afirst light-emitting element 1918 and a plurality of secondlight-emitting elements 19R, 19G, and 19B. The first light-emittingelement 19IR can generate infrared light, and the second light-emittingelements 19R, 19G, and 19B can respectively generate red, green, andblue light (visible light). Hence, the light-emitting module 1 canproject infrared light and visible light onto the object 5 at the sametime.

Moreover, as shown in FIG. 17, the light filter 23 in thelight-receiving module 2 comprises a plurality of light filtering units23U arranged in a matrix. Specifically, each of the light filteringunits 23U has a first filtering portion 231R (infrared-pass filteringportion) and an L-shaped second filtering portion 23C.

Referring to FIG. 18, the image sensor 24 in the light-receiving module2 comprises a plurality of photosensitive units 24U arranged in amatrix. Each of the photosensitive units 24U has a first sensing element241R and a plurality of second sensing elements 24R, 24G, and 24B. Thefirst sensing element 241R can receive infrared light reflected by theobject 5, and the second sensing elements 24R, 24G, and 24B canrespectively receive red, green, and blue light (visible light)reflected by the object 5.

It should be noted that the first sensing elements 241R are locatedcorresponding to the first filtering portions 231R of the light filter23, and the second sensing elements 24R, 24G, and 24B are locatedcorresponding to the second filtering portions 23C of the light filter23. Thus, light reflected by the object 5 can be filtered by the lightfilter 23 and divided into visible light and infrared light. That is,the image sensor 24 can receive infrared light by the first sensingelements 2418, and the image sensor 24 can receive visible light by thesecond sensing elements 24R, 24G, and 24B, so that a 3D model with colorand instance information of the object 5 can be established.

FIG. 19 is a perspective diagram showing a light-emitting module 1 inaccordance with another embodiment of the invention. As shown in FIG.19, two reflecting elements R1 and R2 can be provided in thelight-emitting module 1 of all the aforementioned embodiments, whereinthe reflecting elements R1 and R2 are disposed on the optical pathbetween the light grating element 11 and the light source 19. Here, thelight source 19, the collimating lens L (or other optical pathadjusters), and the reflecting elements R1 and R2 may be received in anaccommodating space 12′ of the housing 12. Light emitted from the lightsource 19 can be sequentially reflected by the reflecting elements R1and R2, and then propagate upward through the light grating element 11.

Still referring to FIG. 19, light emitted from the light source 19propagates through the collimating lens L along a first propagation path(parallel to the Z axis) to the reflecting element R1. Light is thenreflected by the reflecting element R1 and propagates along a secondpropagation path (parallel to the X axis) to the second reflectingelement R2. Subsequently, light is reflected by the second reflectingelement R2 and propagates through the light grating element 11 along athird propagation path (parallel to the Z axis). It should be noted thatthe first and third propagation paths are spaced apart from and parallelto each other. By the arrangement of the two reflecting elements R1 andR2, the total length of the optical path between the light gratingelement 11 and the light source 19 can be increased, so that the size ofthe light-emitting module 1 in the vertical direction can be reduced,and miniaturization of the distance measuring device can be achieved.

FIG. 20 is a perspective diagram showing a light-emitting module 1 inaccordance with another embodiment of the invention. The light-emittingmodule 1 of FIG. 20 is different from FIG. 19 in that the light-emittingmodule 1 comprises two sets of light sources 19, collimating lenses L(or other optical path adjusters), reflecting elements R1 and R2, andlight grating elements 11. Specifically, the two light sources 19 canrespectively emit infrared light and visible light. The light-receivingmodule 2 and the image capturing module 3 can receive infrared light andvisible light which is reflected by the object 5, so as to establish a3D model of the object 5 with color and instance information.

In another embodiment of FIG. 21, the light-emitting module 1 isprovided with a light grating element 11, two reflecting elements R1 andR2, two light sources 19, and two collimating lenses L (or other opticalpath adjusters). The light sources 19 can respectively emit infraredlight and visible light through the collimating lenses L, and light canbe reflected by the reflecting elements R1 and R2 and propagate throughthe light grating element 11.

In some embodiments, as shown in FIGS. 22-24, two reflecting elements R1and R2 may be provided in the light-emitting module 1 (FIG. 22), thelight-receiving module 2 (FIG. 23), or the image capturing module 3(FIG. 24), so as to reduce the size of the distance measuring device inthe vertical direction, wherein the reflecting element R2 comprises aprism. As shown in FIG. 22, the light grating element 11 is attached toa surface of the reflecting element R2. Light emitted from the lightsource 19 can be sequentially reflected by the reflecting elements R1and R2 and propagate upwardly through the light grating element 11.

As shown in FIG. 23, the optical lens 21 of the light-receiving module 2may be attached to a surface of the reflecting element R2. After themeasuring light is reflected by the object 5, it propagates through theoptical lens 21 and is sequentially reflected by the reflecting elementsR2 and R1. Subsequently, light can propagate through the light filter 23to the image sensor 24.

Similarly, as shown in FIG. 24, the optical lens 31 of the imagecapturing module 3 may be attached to a surface of the reflectingelement R2. After the measuring light is reflected by the object 5, itpropagates through the optical lens 31 and is sequentially reflected bythe reflecting elements R2 and R1. Subsequently, light can propagatethrough the light filter 33 to the image sensor 34.

Although some embodiments of the present disclosure and their advantageshave been described in detail, it should be understood that variouschanges, substitutions and alterations can be made herein withoutdeparting from the spirit and scope of the disclosure as defined by theappended claims. For example, it will be readily understood by thoseskilled in the art that many of the features, functions, processes, andmaterials described herein may be varied while remaining within thescope of the present disclosure. Moreover, the scope of the presentapplication is not intended to be limited to the particular embodimentsof the process, machine, manufacture, compositions of matter, means,methods and steps described in the specification. As one of ordinaryskill in the art will readily appreciate from the disclosure of thepresent disclosure, processes, machines, manufacture, compositions ofmatter, means, methods, or steps, presently existing or later to bedeveloped, that perform substantially the same function or achievesubstantially the same result as the corresponding embodiments describedherein may be utilized according to the present disclosure. Accordingly,the appended claims are intended to include within their scope suchprocesses, machines, manufacture, compositions of matter, means,methods, or steps. Moreover, the scope of the appended claims should beaccorded the broadest interpretation so as to encompass all suchmodifications and similar arrangements.

While the invention has been described by way of example and in terms ofpreferred embodiment, it should be understood that the invention is notlimited thereto. On the contrary, it is intended to cover variousmodifications and similar arrangements (as would be apparent to thoseskilled in the art). Therefore, the scope of the appended claims shouldbe accorded the broadest interpretation to encompass all suchmodifications and similar arrangements.

What is claimed is:
 1. A light-emitting module for measuring a distanceto an object, comprising: a housing; an optical path adjuster, disposedin the housing; a first reflecting element, disposed in the housing; asecond reflecting element, disposed in the housing; a light gratingelement; a light source, emitting a measuring light through the opticalpath adjuster, the first and second reflecting elements, and the lightgrating element to the object; and a driving assembly, disposed in thehousing to drive the optical path adjuster, the first reflectingelement, the second reflecting element, or the light grating element tomove relative to the housing.
 2. The light-emitting module as claimed inclaim 1, wherein the measuring light propagates through the optical pathadjuster along a first propagation path to the first reflecting element,and the measuring light is reflected by the first reflecting element andpropagates along a second propagation path to the second reflectingelement.
 3. The light-emitting module as claimed in claim 2, wherein thedriving assembly drives the light grating element to move relative tothe housing in a direction parallel to the first propagation path. 4.The light-emitting module as claimed in claim 2, wherein the firstpropagation path is perpendicular to the second propagation path.
 5. Thelight-emitting module as claimed in claim 2, wherein the measuring lightis reflected by the second reflecting element and propagates through thelight grating element along a third propagation path.
 6. Thelight-emitting module as claimed in claim 5, wherein the thirdpropagation path is spaced apart from the first propagation path.
 7. Thelight-emitting module as claimed in claim 5, wherein the thirdpropagation path is parallel to the first propagation path.
 8. Thelight-emitting module as claimed in claim 1, wherein the optical pathadjuster comprises a collimating lens or a beam expander.
 9. Thelight-emitting module as claimed in claim 1, wherein the light gratingelement comprises a Fresnel lens.
 10. The light-emitting module asclaimed in claim 1, wherein the light-emitting module comprises twolight sources and two optical path adjusters, and the two light sourcesrespectively emit infrared light and visible light through the opticalpath adjusters.
 11. A distance measuring device, comprising: thelight-emitting module as claimed in claim 1; and a light-receivingmodule, receiving the measuring light which is reflected by the objectto obtain distance information of the object.
 12. The distance measuringdevice as claimed in claim 11, wherein the driving assembly drives theoptical path adjuster to move relative to the housing along a firstaxis.
 13. The distance measuring device as claimed in claim 12, whereinthe driving assembly drives the optical path adjuster to move relativeto the housing along a second axis perpendicular to the first axis. 14.The distance measuring device as claimed in claim 11, wherein thedriving assembly drives the optical path adjuster to rotate relative tothe housing around a rotary axis which is perpendicular to the firstaxis.
 15. The distance measuring device as claimed in claim 11, whereinthe optical path adjuster comprises a collimating lens or a beamexpander.
 16. The distance measuring device as claimed in claim 11,wherein the light grating element comprises a Fresnel lens.
 17. Thedistance measuring device as claimed in claim 11, further comprising animage capturing module disposed between the light-emitting module andthe light-receiving module to capture a color image of the object. 18.The distance measuring device as claimed in claim 11, wherein thelight-receiving module has an image sensor having a plurality ofphotosensitive units arranged in a matrix, and each of thephotosensitive units has a first sensing element and a plurality ofsecond sensing elements, wherein the first sensing element receives themeasuring light which is reflected by the object, and the second sensingelements receive a visible light which is reflected by the object. 19.The distance measuring device as claimed in claim 18, wherein each ofthe photosensitive units has a first sensing element and three sensingelements arranged in a matrix.
 20. The distance measuring device asclaimed in claim 19, wherein the light-receiving module has a lightfilter having a plurality of light filtering units arranged in a matrix,and each of the light filtering units has an infrared-pass filteringportion and an infrared-cut filtering portion, corresponding to thefirst and second sensing elements.